4 alternatives to LanguageTool
Compare free and open-source solutions before building your own. Check each option’s license, setup, and limitations.
A fast English grammar checker that stays on your device and mostly keeps its opinions to itself.
Select text anywhere, hit a hotkey, and fix, rewrite, summarize, or obey a custom instruction without opening another tab.
LicenseGPL-3.0
PlatformsOn your machine
InstallationUse the portable Windows ZIP or macOS DMG; Linux currently runs from source
ModelsGemini, native Ollama and any OpenAI-compatible cloud or local endpoint on Windows/Linux; the macOS port also supports OpenAI, Anthropic, Mistral, OpenRouter, Gemini, MLX and Ollama
DataAPI keys and configuration stay on the device; the app does not retain writing or logs, and selected text goes only to the chosen cloud provider unless a local model is used
Limitations compared to LanguageToolIt relies on generative models for corrections, so checks are less deterministic and its multilingual grammar rules and explanations are much thinner than LanguageTool's.
SetupYou must supply an API key or install a local model; macOS needs Accessibility permissions, while Linux installation and Wayland support remain rough
Facts verified 2026-08-14
A LibreOffice extension with long-document checks, style statistics, profiles, and local AI; installing Java is the cover charge.
LicenseLGPL-2.1
PlatformsOn your machine
InstallationInstall LibreOffice 24.2+, Java 17+, then add the downloaded .oxt LibreOffice extension
ModelsLanguageTool rules locally; optional AI rewriting through an OpenAI-compatible API, with local endpoints such as LocalAI specifically supported
DataChecks, profiles and cached document-analysis data run on the local computer; document text is sent away only when a remote LanguageTool or configured AI endpoint is used
Limitations compared to LanguageToolIts LanguageTool-based checks are strong inside LibreOffice, but browser, email, mobile, and cross-application coverage are much weaker than LanguageTool's.
SetupJava 17 and a recent LibreOffice are mandatory, and users must manually install and approve the extension
Facts verified 2026-08-14
Proofread, rewrite, shorten, or change tone almost anywhere, assuming your Apple hardware made the guest list.
LicenseFree, closed source
PlatformsOn your machine or in the cloud
InstallationBuilt into current macOS, iOS and iPadOS; enable Apple Intelligence and let the required models download
ModelsApple on-device foundation models and, for harder requests, Apple Private Cloud Compute; optional ChatGPT is used for Compose
DataEdits are applied to text in the host app rather than kept in a separate Writing Tools library; on-device requests stay local, Private Cloud Compute says request data is not stored, and optional ChatGPT receives the selected content
Limitations compared to LanguageToolIt is convenient on supported Apple hardware, but it covers fewer languages and gives less rule-based grammar explanation and customization than LanguageTool.
SetupRequires Apple Intelligence-compatible Apple hardware, a supported language/region and several gigabytes of downloaded models
Facts verified 2026-08-14
Updated 2026-08-14 · no paid listings
| Tool | License | Setup | Platforms | Stars | Activity |
|---|---|---|---|---|---|
| Harper | Open source | One-click installation | macos, android, browser-extension | 14,200 | 2026-08 |
| Writing Tools | GPL-3.0 | One-click installation | macos, windows | 2,400 | 2026-05 |
| WritingTool | LGPL-2.1 | One-click installation | macos, windows, linux | 65 | 2026-07 |
| Apple Writing Tools | Free, closed source | One-click installation | macos, ios | — | — |
They pay for hosted convenience, premium rules, and cross-device setup. If those points do not matter to you, the options above could save $65.64 per year.
Is there a free alternative to LanguageTool?
Yes: Harper, Writing Tools, WritingTool. This page lists 4 free or open-source options. Check the limitations of each.
Should I build my own LanguageTool?
Our verdict: Buildable. Because the core engine is open source, a technical user can run the grammar checker locally or self-host the server for many use cases. The complete prompt is on the LanguageTool page on Vibe Radar.
